The metal working industry is well aware of the residual existence of a burr, in the form of an integral part of a shaft or the like, remaining on the end of a work piece, such as a shaft, after the shaft has otherwise been cut to its specified length. That is, a machined shaft commonly has a projection or burr remaining on the end of the shaft and which cannot conventionally and easily be removed, other than by grinding, filing, or otherwise removing or cutting the burr from the shaft to render the shaft smooth at that end.
Examples of both prior art work pieces with burrs and of prior art machines for removing the burrs are disclosed in U.S. Pat. Nos. 2,493,039 and 2,838,828 and 3,426,646. All three of these patents show deburring machines different from that disclosed herein, and U.S. Pat. No. 2,493,039 also shows a type of annular burr, rather than a pointed burr which is the type removed in the present invention.
The present invention differs from and improves upon the prior art in that it provides for a deburring machine which utilizes a planar surface having a circular cutting edge thereon and which is rotated past the work piece having the burr. The circular cutting edge presents an optimum shearing type of cut and it is of a dimension smaller than the surface of the work piece whereon the burr is located, so the work piece cannot be inserted into the circular cutting surface for damage of the work piece, and only the burr will be cleanly sheared from the work piece. With this arrangement, an operator can rapidly and conveniently position a work piece on a fixture adjacent the rotating circular cutting edge, and a mass production of the deburring can occur with only a very minimal of attention given to the labor involved of positioning and removing the work pieces in a rapid manner on the fixture while the cutter is being rotated past the work piece. Also, only a very minimum of skill is required in the deburring process, but yet the burr is removed in a neat and clean manner, such as in contrast to a grinding wheel which encounters the entire work piece surface and thereby diminishes it or at least scratches it.
In further contrast to the prior art, U.S. Pat. No. 2,838,828, shows the deburring tool which has a plurality of radial slots presented to the work piece and the burr thereon. However, the edge of the work piece could easily be tilted to penetrate the slots and thereby be damaged. Still further, the number of slots thus formed in the end of the work piece must necessarily be limited in order to retain strength of the tool, and it will be readily understood that only a limited number of the slots can be provided due to material availability in the tool carrying the slots, as compared to the present invention where a large number of circular cutting edges can be provided in the tool, and those circular cutting edges can be extremely close to each other for high speed cutting with only nominal speed of rotation of the cutter itself.
Further, the present invention improves upon the prior art and distinguishes thereover by providing a deburring machine which rapidly and neatly removes the burr from the work piece without endangering or marring the work piece surface carrying the burr, since the work piece surface cannot penetrate the circular cutting edge provided in this invention. Still further, there can be a cutter plate which is rotatably mounted and which has two or more rows of circular cutting edges at different radii from the axis of rotation, and an adjustable fixture can be employed for aligning the work piece with either one of the two circular rows of cutting edges, all so that one plate serves the purpose of either various cutting sizes or of presenting the greatest multiplicity of cutting edges with only one preparation or sharpening of the plate itself.